Pharmacologic Management of Pain for HIV/AIDS
Pharmacologic Guidelines
- An essential principle in using medications to manage pain
is to individualize the regimen to the patient.
- The simplest dosage schedules and least invasive pain management
modalities should be used first.
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Pharmacologic management of mild to moderate cancer pain should
include an NSAID or acetaminophen, unless there is a contraindication.
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When pain persists or increases, an opioid should be added.
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Treatment of persistent or moderate to severe pain should be based
on increasing the opioid potency or dose.
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Medications for persistent cancer-related pain should be
administered on an around-the-clock basis with additional "as-needed" doses,
because regularly scheduled dosing maintains a constant level of drug in the
body and helps to prevent a recurrence of pain.
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Patients receiving opioid agonists should not be given a mixed
agonist-antagonist because doing so may precipitate a withdrawal syndrome and
increase pain.
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Meperidine should not be used if continued opioid use is
anticipated.
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Opioid tolerance and physical dependence are expected with
long-term opioid treatment and should not be confused with addiction.
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The oral route is the preferred route of analgesic administration
because it is the most convenient and cost-effective method of administration.
When patients cannot take medications orally, rectal and transdermal routes
should be considered because they are also relatively noninvasive.
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Intramuscular administration of drugs should be avoided because
this route can be painful and inconvenient, and absorption is not reliable.
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Failure of maximal systemic doses of opioids and coanalgesics
should precede the consideration of intraspinal analgesic systems.
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Because there is great interindividual variation in susceptibility
to opioid-induced side effects, clinicians should monitor for these potential
side effects.
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Constipation is a common problem associated with long-term opioid
administration and should be anticipated, treated prophylactically, and
monitored constantly.
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Naloxone, when indicated for reversal o[[sterling]]-opioid-induced
respiratory depression, should be titrated in doses that improve respiratory
function but do not reverse analgesia.
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Placebos should not be used in the management of cancer pain.
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Patients should be given a written pain management plan.
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Communication about pain,management should occur when a patient is
transferred from one setting to another.
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Drug therapy is the cornerstone of
the many modalities available to manage cancer pain because it is effective,
relatively low risk, inexpensive, and usually of rapid onset. An essential
principle in using medications-to manage cancer pain is to individualize the
regimen to the patient.161
Three major classes of drugs are used alone or, more commonly, in combination
to manage pain in the cancer patient:
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NSAIDs and acetaminophen (APAP).
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Opioid analgesics.
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Adjuvant analgesics.
Before choosing drugs to manage pain or other symptoms, identify the specific
cause(s) of the pain, evaluate its intensity and quality, and then match the
drug to the pain intensity and other characteristics. The simplest dosage
schedules and least invasive pain management modalities should be used first.
After drug therapy has been started, pain should be assessed to determine the
ongoing effectiveness of the analgesic therapy. For opioid analgesics, if pain
relief is inadequate, the dose should be increased until pain relief is
achieved or unacceptable side effects occur. In the case of NSAIDS and adjutant
analgesic drugs, which have ceiling effects to their analgesic efficacy, if the
upper limit of the recommended dose is reached and pain relief is not achieved,
then that particular drug should be discontinued and a second drug in that
class should be used.
Most pain can be managed by oral administration of drugs; however,
difficulty in swallowing, gastrointestinal (GI) disturbances that render drug
absorption unreliable, the amount of drug required, and many other factors may
require alternative routes of administration.103; 189 Table 8 summarizes some of the
advantages and disadvantages of pain therapies.
